Cell Cycle and Cell Division NEET Questions
Cell Cycle and Cell Division NEET Questions are provided here with answers and detailed explanations. These MCQs are important from the NEET exam point of view. By practicing with these questions students will get acquainted with the key concepts which must be prepared to score high marks in the NEET and Board Exams.
A cell cycle is a series of events that takes place in a cell as it grows and divides. In eukaryotes, the cell cycle consists of four discrete phases: G1, S, G2, and M. The S or synthesis phase is when DNA replication occurs, and the M or mitosis phase is when the cell divides. The other two phases – G1 and G2, the so-called gap phases – are less dramatic but equally important.
The cell plate grows from the center toward the cell walls. New cell walls are made from the vesicle contents. Prophase is the first stage of mitosis. In prophase the chromosomes condense, the nucleolus disappears, and the nuclear envelope breaks down. Metaphase is the best time to count and study the number and morphology of chromosomes.
The stage in which daughter chromosomes move toward the poles of the spindle is Anaphase. Cytokinesis is the process by which the cytoplasm of the parent cell divides into two daughter cells. Whereas karyokinesis is a process where the nucleus of the parent cell divides into two daughter nuclei. The stage between two meiotic divisions is called interkinesis and is generally short-lived. Here the cell undergoes a period of rest. No DNA replication and no gene duplication occur during this stage. It is important for bringing true haploidy into daughter cells.
Endomitosis is the process of chromosome divides or doubles without nuclear division which leads to the formation of a polyploidy nucleus where one nucleus will have multiple sets of chromosomes. The most basic function of the cell cycle is to duplicate accurately the vast amount of DNA in the chromosomes and then segregate the copies precisely into two genetically identical daughter cells.
Cell Cycle and Cell Division NEET Questions
1. Which of the following is the longest phase of the cell cycle?
(1) Prophase
(2) Interphase
(3) Telophase
(4) M‑phase
Answer: 2 – Interphase
Explanation: Interphase (G₁, S, G₂) occupies the majority of the cell cycle, preparing the cell for division.
Read: NEET Chapterwise MCQ
2. First gap phase in the cell cycle is________
(1) between mitosis and DNA replication
(2) between DNA replication and DNA separation
(3) between karyokinesis and cytokinesis
(4) between DNA replication and second gap phase
Answer: 1
Explanation: G₁ occurs right after mitosis and before DNA synthesis (S‑phase).
3. Interphase includes_______
(1) G₀, G₁, S, G₂
(2) Prophase, Metaphase, Anaphase, Telophase
(3) Cytokinesis
(4) Mitosis / M‑phase
Answer: 1
Explanation: Interphase includes the resting phase (G₀), growth (G₁), DNA synthesis (S), and preparation for mitosis (G₂).
4. The two chromatids of a metaphase chromosome represent_______
(1) Replicated DNA to be separated at anaphase
(2) Nonhomologous chromosomes joined at the centromere
(3) Pair of homologous chromosomes
(4) Maternal and paternal chromosomes joined at the centromere
Answer: 1
Explanation: Chromatids are identical copies produced during DNA replication, linked at the centromere.
5. The stage during which separation of paired homologous chromosomes begins is_________
(1) Pachytene
(2) Diplotene
(3) Diakinesis
(4) Zygotene
Answer: 2
Explanation: In diplotene, homologous chromosomes begin to separate but remain connected at chiasmata.
6. For chromosome counting in onion root tips, which stage is best?
(1) Prophase
(2) Anaphase
(3) Telophase
(4) Metaphase
Answer: 4
Explanation: Chromosomes are clearly visible and aligned during metaphase, making counting easy.
7. In mitosis, the nuclear envelope and nucleolus disappear during________
(1) Metaphase
(2) Interphase
(3) Prophase
(4) Telophase
Answer: 3
Explanation: The nuclear membrane and nucleolus disassemble in prophase to allow spindle attachment.
8. For G₂ checkpoint qualification, cells require_________
(1) Sufficient size
(2) Complete and accurate DNA replication
(3) Nucleotide stockpile
(4) Mitotic spindle attachment
Answer: 2
Explanation: G₂ ensures DNA duplication is done correctly before mitosis begins.
9. Chromosomes first become distinct under light microscopy during_________
(1) Prometaphase
(2) Prophase
(3) Anaphase
(4) Metaphase
Answer: 2
Explanation: Chromatin condenses into visible chromosomes at prophase.
10. Chromosome duplication without nuclear division refers to_______
(1) Mitosis
(2) Endomitosis
(3) Meiosis
(4) Androgenesis
Answer: 2
Explanation: Endomitosis involves chromosome doubling without mitosis, leading to polyploidy
11. Recombination of genes occurs at__________
(1) Prophase I in meiosis
(2) Prophase II in meiosis
(3) Metaphase II in meiosis
(4) Prophase in mitosis
Answer: 1
Explanation: Genetic recombination (crossing over) occurs during prophase I.
12. The stage between two meiotic divisions is called interkinesis and__________
(1) Short-lived and followed by prophase II
(2) Involves duplication of genes and centrioles
(3) Followed by prophase I
(4) Long-lived
Answer: 1
Explanation: Interkinesis is a brief resting period between meiosis I and II.
13. A cell entering mitotic phase (M‑phase) is________
(1) always haploid, duplicated chromosomes
(2) haploid or diploid, duplicated chromosomes
(3) haploid or diploid, duplicated or unduplicated chromosomes
(4) always diploid, unduplicated chromosomes
Answer: 2
Explanation: Mitosis can occur in both haploid and diploid cells; chromosomes are duplicated before M-phase.
14. Synaptonemal complex is visible from________
(1) Zygotene to pachytene
(2) Leptotene to diplotene
(3) Zygotene to metaphase
(4) Pachytene to diplotene
Answer: 1
Explanation: The synaptonemal complex, which pairs homologs, forms between zygotene and pachytene.
15. Correct match is________
(1) Leptotene – formation of bivalents
(2) Diplotene – chiasmata appear
(3) Pachytene – chiasmata formation
(4) Zygotene – bouquet formation
Answer: 2
Explanation: Chiasmata (crossing over points) become visible in diplotene.
16. In which stage are chromosomes thin and thread-like?
(1) Zygotene
(2) Leptotene
(3) Pachytene
(4) Diakinesis
Answer: 2
Explanation: Chromosomes are long and thin in leptotene before condensation.
17. Meiosis involves________
(1) One nuclear & one chromosome division
(2) Two nuclear & one chromosome division
(3) One nuclear & two chromosome division
(4) Two nuclear & two chromosome division
Answer: 2
Explanation: Meiosis involves two nuclear divisions (I & II) and one DNA replication.
18. In meiosis, centromeres separate during_________
(1) Anaphase II
(2) Metaphase I
(3) Anaphase I
(4) Prophase II
Answer: 1
Explanation: Sister chromatids separate during anaphase II.
19. If a cell in prophase has 100 DNA units & 50 chromosomes, in anaphase it will have________
(1) 200 DNA & 100 chromosomes
(2) 100 DNA & 50 chromosomes
(3) 100 DNA & 100 chromosomes
(4) 50 DNA & 25 chromosomes
Answer: 3
Explanation: Chromatids separate, doubling chromosome count to 100; DNA remains 100 units.
20. During which phase is cellular component synthesis and assembly done?
(1) S
(2) G₂
(3) G₁
(4) M
Answer: 3
Explanation: G₁ is the growth phase, producing proteins, organelles, and materials for DNA replication.
21. Spindle fibers attach to_________
(1) Telomere
(2) Kinetochore
(3) Centromere
(4) Kinetosome
Answer: 2
Explanation: Spindle microtubules bind the kinetochore, a protein complex on centromeres.
22. In prophase, which chromosome type is present?
(1) 2‑chromatid
(2) 1‑chromatid
(3) 4‑chromatid
(4) 8‑chromatid
Answer: 1
Explanation: Chromosomes consist of two sister chromatids joined at the centromere.
23. A somatic cell post‑S phase vs. a gamete of same species has________
(1) Same chromosome number, double DNA
(2) Twice chromosomes, quadruple DNA
(3) Quadruple chromosomes, double DNA
(4) Twice chromosomes, double DNA
Answer: 2
Explanation: After S, a diploid somatic cell has 2n chromosomes and 4C DNA; haploid gamete has n chromosomes and 1C DNA
24. Sequence in meiosis events:
(a) Crossing over
(b) Synapsis
(c) Terminalization of chiasmata
(d) Nucleolus disappearance
(1) b, c, d, a
(2) b, a, d, c
(3) b, a, c, d
(4) a, b, c, d
Answer: 3
Explanation: Synapsis → Crossing over → Chiasmata terminalization → Nucleolus disappears.
25. Correct mitosis sequence:
(1) Condensation → envelope disassembly → equator alignment → centromere division → segregation → telophase
(2) Condensation → crossing‑over → …
(3) Condensation → equator alignment → centromere division → …
(4) Condensation → envelope disassembly → crossing‑over → …
Answer: 1
Explanation: That’s the accurate step-by-step chronology of mitosis.
26. Defective APC in a human cell results in________
(1) Chromosome fragmentation
(2) Chromosome segregation failure
(3) Chromatid recombination
(4) Chromosome condensation failure
Answer: 2
Explanation: APC triggers sister chromatid separation; without it, they fail to segregate.
27. Crossing over in meiosis is initiated at________
(1) Pachytene
(2) Leptotene
(3) Zygotene
(4) Diplotene
Answer: 1
Explanation: Recombination events occur in pachytene.
28. DNA synthesis during cell growth occurs in________
(1) G₂
(2) M
(3) S
(4) G₁
Answer: 3
Explanation: S‑phase is when DNA replication happens.
29. Which checkpoint responds to stalled replication forks?
(1) M
(2) G₂/M & M
(3) G₁/S
(4) G₂/M
Answer: 4
Explanation: DNA replication checkpoints (G₂/M) halt progression if replication is incomplete.
30. Complex of synapsed homologous chromosomes is called________
(1) Axoneme
(2) Equatorial plate
(3) Kinetochore
(4) Bivalent
Answer: 4
Explanation: Two homologs paired during meiosis form a bivalent (tetrad).
31. When does diploid cell’s DNA become fourfold of haploid?
(1) G₁
(2) S
(3) G₂, S & G₂
(4) G₀
Answer: 2
Explanation: During S‑phase, DNA replicates from 2C to 4C.
32. When does DNA remain at 4C level?
(1) G₀ & G₁
(2) G₁ & S
(3) G₂ only
(4) G₂ & S
Answer: 4
Explanation: DNA is at 4C during S replication and up to mitosis.
33. In S-phase of the cell cycle________
(1) DNA amount doubles
(2) DNA remains constant
(3) Chromosome number increases
(4) DNA halves
Answer: 1
Explanation: DNA synthesis doubles the genetic material.
34. Recombinase is required in meiosis during________
(1) Pachytene
(2) Zygotene
(3) Diplotene
(4) Diakinesis
Answer: 1
Explanation: Recombinase facilitates crossing over during pachytene.
35. In which meiotic stage do homologs separate while sister chromatids remain joined?
(1) Anaphase I
(2) Anaphase II
(3) Metaphase I
(4) Metaphase II
Answer: 1
Explanation: Homologs split in anaphase I; sister chromatids remain until II.
36. Which statement is wrong about G₁ phase?
(1) G₁ followed by mitosis
(2) Metabolically active
(3) Cell grows continuously
(4) No DNA replication
Answer: 1
Explanation: G₁ precedes S‑phase, not mitosis directly.
37. Correct mitosis statement:
(1) Chromatids separate but stay central in anaphase
(2) Chromatids move during telophase
(3) Golgi and ER still visible end‑prophase
(4) Chromosomes align at metaphase plate
Answer: 4
Explanation: Chromosomes align centrally during metaphase.
38. At metaphase, chromosomes attach to spindle via_________
(1) Centromere
(2) Satellites
(3) Secondary constrictions
(4) Kinetochores
Answer: 4
Explanation: Microtubules bind kinetochores at centromeres.
39. Which is NOT a feature of meiosis?
(1) Two DNA replications
(2) Recombination
(3) Sister chromatid separation in anaphase II
(4) Nuclear envelope breaks in prophase
Answer: 1
Explanation: Meiosis only involves one round of replication before two divisions.
40. Recombinase functions during________ in gamete formation
(1) Prophase I
(2) Prophase II
(3) Metaphase I
(4) Anaphase II
Answer: 1
Explanation: Enzyme needed during crossing over in prophase I.
41. If 46 chromosomes are at each mitotic pole in telophase, how many chromatids were at metaphase?
(1) 23
(2) 46
(3) 92
(4) 69
Answer: 3
Explanation: Each chromosome has 2 chromatids → 46 × 2 = 92.
42. A chemical blocking microfilaments in mouse cells impairs________
(1) Spindle formation
(2) Cytokinesis
(3) Chromosome duplication
(4) Homolog pairing
Answer: 2
Explanation: Microfilaments (actin) are essential for cytokinesis (cleavage furrow).
43. Number of chromosome pairs at metaphase‑of diploid plant (2n=50):
(1) 50
(2) 100
(3) 75
(4) 25
Answer: 4
Explanation: A diploid cell with 50 chromosomes (=25 pairs), so 25 are found.
44. Number of meiotic divisions needed for 500 zygotes?
Answer: 1 = 625 divisions
Explanation: Male gametes: 1 division = 4 sperm; females: 1 gamete per division.
500 zygotes need 500 eggs → 500 divisions; 500 eggs require 500 sperm groups which need 125 sperm sets = 125 divisions. Summing both types yields 625 divisions total.
45. Chromatids per chromosome at anaphase are________
(1) 1 in mitosis, 1 in meiosis I, 2 in meiosis I
(2) 1 in mitosis, 2 in meiosis I, 1 in meiosis II
(3) 2 in mitosis, 1 in meiosis I, 2 in meiosis II
(4) 2 in mitosis, 2 in meiosis I, 2 in meiosis II
Answer: 2
Explanation: At anaphase: 1 chromatid separated each into daughters.
46. Incorrect phase–function match?
(1) G₂ – cytoplasmic growth
(2) G₁ – organelle duplication
(3) Interphase – cell division prep
(4) DNA synthesis – doubling phases count
Answer: 4
Explanation: DNA synthesis duplicates DNA content, not phases.
47. Incorrect meiosis statements?
(A) Single DNA replication
(B) Four haploids after meiosis‑I
(C) Meiosis in diploids
(D) Yeast cell cycle lasts ~90 min
Answer: 3 (Only B)
Explanation: Haploid cells are created after meiosis II, not I.
48. Meiosis involves________
(1) homolog pairing & recombination between sister chromatids of non‑homologs
(2) homolog pairing & recombination between non‑sister chromatids of homologs
(3) nonhomolog pairing & recomb between non‑sister of homologs
(4) homolog pairing & recomb between sister chromatids of homologs
Answer: 2
Explanation: Crossing-over occurs between non-sister chromatids of homologous chromosomes.